Field of the Invention
This invention relates to triazole derivatives and to fluid compositions containing same which are specially designed for use between two relatively moving surfaces for reducing friction therebetween and preserving the surfaces. More specifically, the invention discloses improved diesel lubricant compositions which impart superior oxidative stability and corrosion control to a medium speed, diesel engine oil containing a calcium carbonate overbased sulfurized calcium alkylphenolate.
Earlier formulations of this type contained various calcium sulfurized alkylphenolates which were designed to provide the finished oil with improved corrosion protection and/or oxidative stability. These phenolates included sulfurized CO.sub.2 -blown, double neutralized, normal calcium alkylphenolate, 2/1 overbased Ca(OH).sub.2 sulfurized calcium alkylphenolate and calcium reagent neutralized, sulfurized calcium alkylphenolate overbased by the hydrolysis of calcium reagent and blown with CO.sub.2 for complete carbonation. These all were made by a process which employed a solvent recovery procedure which was expensive and wherein some of the byproducts that were trapped in the filter cake were hazardous to the environment upon disposal and did not meet EPA requirements. Accordingly, these detergents were replaced by calcium sulfurized phenolates made by a process utilizing lime as the source of calcium whereby the solvents system is eliminated and the disposed residue meets EPA regulations. These phenolates can be denominated 1/1 calcium carbonate overbased sulfurized calcium alkylphenolates and 2/1 overbased sulfurized calcium alkylphenolates containing calcium sulfonate. These detergents-dispersants do not however, provide the corrosion protection or oxidative stability medium speed diesel engine formulations that the calcium reagent produced phenolates provided. In order to attain the original performance with the lime prepared phenolates, it is necessary now to supplement the formulation with a corrosion and/or oxidation inhibitor.